561286639 has 2 divisors, whose sum is σ = 561286640. Its totient is φ = 561286638.

The previous prime is 561286613. The next prime is 561286667. The reversal of 561286639 is 936682165.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 561286639 - 2⁷ = 561286511 is a prime.

It is a super-3 number, since 3×561286639³ (a number of 27 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (561286699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280643319 + 280643320.

It is an arithmetic number, because the mean of its divisors is an integer number (280643320).

Almost surely, 2^561286639 is an apocalyptic number.

561286639 is a deficient number, since it is larger than the sum of its proper divisors (1).

561286639 is an equidigital number, since it uses as much as digits as its factorization.

561286639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 466560, while the sum is 46.

The square root of 561286639 is about 23691.4887459611. The cubic root of 561286639 is about 824.8878397875.

The spelling of 561286639 in words is "five hundred sixty-one million, two hundred eighty-six thousand, six hundred thirty-nine".